00000000: 22 20 20 20 20 20 20 20 20 20 20 20 20 20 20 CF |" .|
00000010: 50 43 4F 44 45 3A 20 D2 D4 D3 0D 22 20 20 20 20 |PCODE: ...." |
00000020: 20 20 20 20 20 20 20 20 20 20 2D 2D 2D 2D 2D 2D | ------|
00000030: 2D 2D 2D 2D 2D 0D 22 0D 22 0D 22 CF 50 45 52 41 |-----.".".".PERA|
00000040: 54 49 4F 4E 3A 20 20 D2 D4 D3 20 54 41 4B 45 53 |TION: ... TAKES|
00000050: 20 32 20 42 59 54 45 53 20 46 52 4F 4D 20 54 48 | 2 BYTES FROM TH|
00000060: 45 0D 22 53 54 41 43 4B 2C 20 20 49 4E 43 52 45 |E."STACK, INCRE|
00000070: 4D 45 4E 54 53 20 20 54 48 45 20 20 52 45 53 55 |MENTS THE RESU|
00000080: 4C 54 2C 20 20 20 41 4E 44 0D 22 4A 55 4D 50 53 |LT, AND."JUMPS|
00000090: 20 54 4F 20 54 48 45 20 41 44 44 52 45 53 53 20 | TO THE ADDRESS |
000000A0: 46 4F 55 4E 44 20 42 59 20 20 50 55 54 54 49 4E |FOUND BY PUTTIN|
000000B0: 47 0D 22 49 54 20 49 4E 54 4F 20 54 48 45 20 50 |G."IT INTO THE P|
000000C0: 52 4F 47 52 41 4D 20 20 43 4F 55 4E 54 45 52 2E |ROGRAM COUNTER.|
000000D0: 20 20 20 C9 54 20 20 49 53 0D 22 53 49 4D 49 4C | .T IS."SIMIL|
000000E0: 41 52 20 54 4F 20 D2 D4 C9 2C 20 42 55 54 20 20 |AR TO ..., BUT |
000000F0: 44 4F 45 53 20 20 4E 4F 54 20 20 43 48 41 4E 47 |DOES NOT CHANG|
00000100: 45 0D 22 54 48 45 20 20 20 50 52 4F 43 45 53 53 |E."THE PROCESS|
00000110: 4F 52 20 20 20 46 4C 41 47 53 2C 20 20 20 53 49 |OR FLAGS, SI|
00000120: 4E 43 45 20 20 20 20 41 4E 0D 22 49 4D 50 4F 52 |NCE AN."IMPOR|
00000130: 54 41 4E 54 20 46 45 41 54 55 52 45 20 20 4F 46 |TANT FEATURE OF|
00000140: 20 20 53 55 42 52 4F 55 54 49 4E 45 53 20 20 49 | SUBROUTINES I|
00000150: 53 0D 22 54 48 41 54 2C 20 20 4F 4E 20 20 52 45 |S."THAT, ON RE|
00000160: 54 55 52 4E 2C 20 20 46 4C 41 47 53 20 20 53 48 |TURN, FLAGS SH|
00000170: 4F 55 4C 44 20 20 20 42 45 0D 22 55 53 41 42 4C |OULD BE."USABL|
00000180: 45 2E 20 20 C1 4C 53 4F 2C 20 55 4E 4C 49 4B 45 |E. .LSO, UNLIKE|
00000190: 20 D2 D4 C9 20 49 4E 20 57 48 49 43 48 20 54 48 | ... IN WHICH TH|
000001A0: 45 0D 22 41 44 44 52 45 53 53 20 53 41 56 45 44 |E."ADDRESS SAVED|
000001B0: 20 49 53 20 54 48 45 20 41 44 44 52 45 53 53 20 | IS THE ADDRESS |
000001C0: 54 4F 20 52 45 54 55 52 4E 0D 22 54 4F 2C 20 D2 |TO RETURN."TO, .|
000001D0: D4 D3 20 4D 55 53 54 20 49 4E 43 52 45 4D 45 4E |.. MUST INCREMEN|
000001E0: 54 20 54 48 45 20 41 44 44 52 45 53 53 20 20 49 |T THE ADDRESS I|
000001F0: 54 0D 22 46 45 54 43 48 45 53 20 46 52 4F 4D 20 |T."FETCHES FROM |
00000200: 54 48 45 20 53 54 41 43 4B 2C 20 20 57 48 49 43 |THE STACK, WHIC|
00000210: 48 20 20 50 4F 49 4E 54 53 0D 22 54 4F 20 54 48 |H POINTS."TO TH|
00000220: 45 20 20 53 45 43 4F 4E 44 20 20 42 59 54 45 20 |E SECOND BYTE |
00000230: 20 41 46 54 45 52 20 20 41 20 20 27 CA D3 D2 27 | AFTER A '...'|
00000240: 2E 0D 22 28 D0 52 45 53 55 4D 41 42 4C 59 2C 20 |.."(.RESUMABLY, |
00000250: 54 48 45 20 43 48 49 50 20 55 53 45 53 20 54 48 |THE CHIP USES TH|
00000260: 45 20 52 4F 55 54 49 4E 45 0D 22 46 4F 52 20 C2 |E ROUTINE."FOR .|
00000270: D2 CB 20 41 4E 44 20 46 4F 52 20 CA D3 D2 20 49 |.. AND FOR ... I|
00000280: 4E 20 43 4F 4D 4D 4F 4E 29 2E 0D 22 0D 22 5A 5A |N COMMON).."."ZZ|
00000290: 5A 5A 5A 0D 0D 80 0D 0A |ZZZ..... |
" OPCODE: RTS."
-----------."."."OPERATION: RTS TAKES
2 BYTES FROM THE."STACK, INCREMENTS T
HE RESULT, AND."JUMPS TO THE ADDRESS
FOUND BY PUTTING."IT INTO THE PROGRAM
COUNTER. IT IS."SIMILAR TO RTI, BUT
DOES NOT CHANGE."THE PROCESSOR FLA
GS, SINCE AN."IMPORTANT FEATURE OF
SUBROUTINES IS."THAT, ON RETURN, F
LAGS SHOULD BE."USABLE. ALSO, UNLIKE
RTI IN WHICH THE."ADDRESS SAVED IS THE
ADDRESS TO RETURN."TO, RTS MUST INCREMEN
T THE ADDRESS IT."FETCHES FROM THE STAC
K, WHICH POINTS."TO THE SECOND BYTE
AFTER A 'JSR'.."(PRESUMABLY, THE CHIP
USES THE ROUTINE."FOR BRK AND FOR JSR I
N COMMON).."."ZZZZZ.....
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